6.ruby控制语句
def sounds(str)
if str == "mimi"
puts "It is a cat."
elsif str == "wowo"
puts "It is a dog."
elsif str == "gaga"
puts "It is a duck."
else
puts "unknown."
end
end
7.循环
(1)while ,用于自由指定条件
i=0
sum=0
while i<=100
sum += i
i += 1
end
i
=>101
sum
=>5050
(2)until语句 (当条件不成立的时候执行)
i = 5
until i<5
puts "haha"
i -= 1
end
(3)for 用于
i=0
sum=0
for i in 0 .. 100
sum += i
end
sum
=>5050
(4)times方法,用于指定循环次数
5.times{
print("Ruby!n')
}
5.times do
puts "aa"
end
do end <==> {}
(5)each .用于从对象中逐个取元素
i=0
a = %w{Perl Python Ruby Scheme}
a.each{|lang|
i +=1
if i ==3
break
end
puts "#{i},#{lang}"
}
break 跳出循环
next 跳到下一次循环,有点像continue
redo 以相同的条件进行此次循环
(6)LOOP
loop{
break/next/redo
}